Whatever the origins of the surname he appears to be British
Name: DE SANDOVAL-SIEVIER, ROBERT ADRIAN
Initials: R A
Nationality: United Kingdom
Rank: Sub-Lieutenant
Regiment/Service: Royal Navy
Unit Text: H.M.S. Daedalus
Secondary Regiment: Royal Air Force
Secondary Unit Text: serving with 103 Sqdn.
Age: 22
Date of Death: 09/09/1940
Additional information: Son of Adrian and Muriel de Sandoval-Sievier, of Chiswick, Middlesex
Casualty Type: Commonwealth War Dead
Grave/Memorial Reference: Bay 1, Panel 3
Memorial:
LEE-ON-SOLENT MEMORIAL